Various tools for acquiring the three-dimensional shapes of objects have been suggested, but the functions of all the tools are limited to those under certain conditions. In conventional cases, operators adjust imaging environments and methods so that the conditions are satisfied. However, it is not possible to control positions and orientations with high accuracy. Therefore, a computation time might become longer due to a process of combining acquired data, and the accuracy of the results of positioning might be low. It is also difficult to eliminate blurring, noise, and the like caused by the imaging conditions from digitized data, and this difficulty leads to a longer data preparation process. Further, in digital data of the object that shows both the three-dimensional shape of the object and the pattern on the surface of the shape, the texture information showing the pattern on the surface is often data with higher definition than the shape information, and there is a demand for capturing more precise images.
Meanwhile, Patent Literature 1 discloses a portable three-dimensional shape measuring apparatus that can be carried around and enables quick acquisition of high-precision three-dimensional shape data. In this portable three-dimensional shape measuring apparatus, a three-dimensional shape sensor capable of detecting a three-dimensional shape is attached as a shape sensor to the tip of an articulated arm standing on a base, and the three-dimensional shape sensor is made to face a measurement region on a measurement target in a non-contact manner, with the three-dimensional position and the posture thereof being adjusted. While the three-dimensional shape sensor is in a resting state, three-dimensional shape data of the measurement target is output from the shape sensor as a result of surface scanning. Patent Literature 2 discloses a method of generating three-dimensional shape data from a plurality of images. According to this method, the position and the orientation of the camera that has captured the images can be calculated, and thus, a three-dimensional shape that is not affected by the accuracy of the position and the orientation of the camera can be generated. In Patent Literature 3, imaging is performed with a single camera under various lighting conditions, and the three-dimensional shape of an object and texture information about the object are generated. As a single camera is used, positional displacement between the three-dimensional shape and the texture due to distortion of the lens is avoided.